There’s an article at Search Engine Land which explains what this tool does and why it exists.

You will also notice, Google is attaching a warning with using this tool. Here’s the problem. For the past 13 years, people conducting SEO (creating links for the express purposes of getting a high ranking in Google) have been placing links on blogs they have no control over. There have been many wonderful services over the years automating this process. As I have been saying for the past 18 months, this game is over.

Winter is here.

Because the vast majority of these WordPress Blogs are operated by robots. It’s impossible for people who initially created these links to remove them. Google must love the delicious irony.

Even more ironic, is the way if the SEO firms are now charging for removal of the links they created in the first place!